Recently, a fingerprint identification technology has been widely applied to a variety of electronic products. By using the fingerprint identification technology, the user's fingerprint can be inputted into an electronic product and saved in the electronic product. For unlocking the electronic product, the user has to input the fingerprint through a fingerprint identification module. The way of unlocking the electronic product by the fingerprint identification technology is faster and more user-friendly than the way of manually inputting the password. Consequently, the fingerprint identification technology is favored by many users, and the demands on the fingerprint identification module are gradually increased.
FIG. 1 schematically illustrates a structure of a conventional fingerprint identification module. As shown in FIG. 1, the conventional fingerprint identification module 1 comprises a circuit board 11, a fingerprint sensor 12 and a covering plate 13. The fingerprint sensor 12 is disposed on the circuit board 11. Moreover, the fingerprint sensor 12 is electrically connected with the circuit board 11 to acquire electric power from the circuit board 11. The covering plate 13 is disposed on the fingerprint sensor 12. The covering plate 13 is used as a contact interface between the user's finger and the fingerprint sensor 12. Moreover, the covering plate 13 can protect the surface of the fingerprint sensor 12. Consequently, even if the fingerprint sensor 12 is frequently contacted with the user's finger, the surface of the fingerprint sensor 12 is not damaged. When the user's finger is placed on the covering plate 13, the fingerprint image of the user's finger is sensed by the fingerprint sensor 12. The fingerprint image sensed by the fingerprint sensor 12 is transmitted to the electronic device through the circuit board 11 so as to be recognized.
For preventing moisture or dust from entering the region between the circuit board 11 and the fingerprint sensor 12, the periphery of the junction between the circuit board 11 and the fingerprint sensor 12 is usually coated with an isolation material such as glue 14. FIG. 2 schematically illustrates the device of dispensing glue on the periphery of the junction between the circuit board and the fingerprint sensor during the manufacturing process of the conventional fingerprint identification module. As shown in FIG. 2, the production line of the conventional fingerprint identification module 1 comprises a working platform 9 and a dispenser 8. Firstly, plural assemblies of circuit boards 11 and corresponding fingerprint sensors 12 are fixed on the working platform 9. Then, a dispensing needle 81 is moved to a position over a circuit board 11a under control of the dispenser 8. Then, the dispensing needle 81 is moved downwardly and contacted with the periphery 15a of the junction between the circuit board 11a and the overlying fingerprint sensor 12a, and a glue dispensing operation is performed on the periphery 15a. After the glue dispensing operation is completed, the dispensing needle 81 is moved to a position over a next circuit board 11b under control of the dispenser 8. Then, the dispensing needle 81 is moved downwardly and contacted with the periphery 15b of the junction between the circuit board 11b and the overlying fingerprint sensor 12b, and a glue dispensing operation is performed on the periphery 15b. The above steps are repeatedly done until the peripheries of the junctions between the circuit boards and the overlying fingerprint sensors on the working platform 9 are all coated with the glue 14, which is used for isolating the moisture or dust. Afterwards, the circuit boards 11 are removed from the working platform 9, and placed into a baking apparatus (not shown). Consequently, the glue 14 between each circuit board 11 and the overlying fingerprint sensor 12 is solidified.
However, the above process still has two drawbacks. Firstly, the travelling distance of the dispensing needle 81 is too long. That is, the travelling distance covers the layout range D of all circuit boards 11 (see FIG. 2). Consequently, the production line occupies a lot of space. Secondly, the process is very complicated. For example, after the glue dispensing operations are completed, the circuit boards 11 are sequentially removed from the working platform 9 and then sequentially placed into the baking apparatus. After the baking process is completed, the circuit boards 11 are sequentially removed from the baking apparatus. In other words, the method of manufacturing the fingerprint identification module needs to be further improved.